Brake



Oct. 5, 1943. J. A. FORBES I 2,330,879

BRAKE v .Filed July 21, 1941 2 Sheets-Sheet 1 H03. 1 A NVENTOR;

- I I JOSEPH A.F)RBES BY ATTORNEYS Oct. 5, 1943. 1 J. A, FORBES 2,330,879

' BRAKE v Filed July 21, 1941 '2 Sheets-Sheet 2 nvvszvron.

' JOSEPH FORBES Patented Oct. 5, 1943 BRAKE Joseph A. Forbes, Detroit, Mich, assignorto Kelsey-Hayes Wheel Company, Detroit, Mich, a

corporation of'D'elaware Application JulyZl, 1941 ,Serial No. 403,434

9 Claims.

The invention relates to brakes and refers more particularly to internal brakes adapted for use with motor vehicle and airplane wheels.

The invention has for an object to provide a simple construction of brake which is powerful in action. i

The invention has for another object toprovide a brake of the momentum type in which friction members are adapted to be forced against a brake drum by means utilizing the torque of the friction members after the brake has been applied.

The invention has for a further object to provide a brake inwhich a transversely split ring is expansible to force the friction members against the brake drum and the friction members are operatively connected to'the ring to transfer their torque to the ring. to increase the expanding force applied to the ring. p I

With these and other objects in view, themvention resides in the novel features of construction and combinations and arrangements of parts as more fully hereinafter set forth.

In the drawings:

Figure 1 is an elevation of a brake embodyin my invention;

Figures 2, 3 and 4 are cross sections on 'the lines 22, 33 and 4--4, respectively, of Figure 1;

Figure 5 is a view similar to Figure 1 showing another embodiment of myinvention. V

-The brake, as illustrated in Figures 1 to 4 inclusive, comprises the brake drum l adaptedto be secured to a wheel ofa motor vehicle, airplane, or the like, and the internal friction device 2 within and engageable with the brake flange 3 of the drum when applied by the actuator 4. I

' The internal friction device comprises the friction members 5 and 6 and the expansible transversely splitlring 1 for forcing the friction members against the brake flange when expanded by means of the actuator 4. The friction members are alike and each comprises a T-section shoehaving the radial web Band the axialflange 9 to which is secured the lining I ll engageable with the brake flange 3. 'The ring I is'of U-section and embraces the webs 8 of the brake shoes, the legs l l of thering being at oppositesides of the webs. The legs are preferably formed with the angularly spaced radially outwardly extendingprojections I2 engageable with the axial flanges of the shoes to force the latter outwardly at angu: larly spaced zones against the brake flange of the the axial flanges are continuous from end to end.

The ends of the ring have'se'cured thereto the reinforcements reach of whichfis'forme'd of a pair of fashioned plates at oppositeside's" ofthe ring and extending peripherally beyond the intermediate ends of the webs of one'of the brake shoes. The ends of these plates are riveted to the endsof the ring and'the plates are formed with generally radially inwardly extending portions [radially inwardly of the ring and riveted together to form the projections l5. The actuator 4, as shown, is' a wheel eylindercf usual construction mounted on the backing plate for the brake drum and located between the projections 15. The wheel cylinder has the rods 16 which are connected to its pistons and Whichabut. the projections l5 and arev adapted when braking liquid is forced intothe wheel cylinder to relativelymOve the "ends of the ring away from eachpther through their reinforcements to expand the ring.

ll are anchor: pins secured tothe backing plate and engageable with the. projections l5 radially outwardly of the zone of engagement of the piston rods with the projections. The anchor pins serve to anchor .thev ring at either end depending upon the direction of rotation of the brake drum.

For the purpose of utilizing the torque of each of the friction members to increase the expand.-

iing force applie d to thering, each of the friction membersjis connected tothe ring by the transverse hollowL pin I; which extends. through the web OfjtheEfrictiOn member and the legs 'of the ring. TA rivet l9 extends through the hollow pin and isiheaded over at the ends thereof. ,The connections betweenthe friction members andring are located near the trailin ends of the friction members.

f In operation, assuming the brake drumtobe rotating in the direction indicated by the arrow in Figure 1, it will be seen that when braking liquid is forced under pressure into the wheel cylinder 4 the ends of. the ring 1 are initially pread apart, but as soon as the. upper friction member 5 comes'into contact with the brake flange 3jof the drum theright hand end ofthe ring will become anchored upon, its anchor pin-l! and the left hand end of the ring will continue moving away; from its anchor pin l'l, the ring] beingexpanded atthis timetopforce the friction members at angularly fspacedIzbnes against the brake flange. The friction members will wrapincut away midway between their ends at I3, but

to contact with the. brake flange and immediately after'the initial contact the torque of the portion of the "upper friction member between the wheel cylinder 4 and the connection I8 is transferred .stantial amount of .wrap

member 'is'carried over to the lefthand end oftheupper friction member from which time similar cycles continue until the brake is released by The I leasing the pressure of the braking liquid entep ing the wheel cylinder. The internal friction device can then be returned to itsj-normaljor ofi position which is facilitated "by reason cf 'trhein-f herent resiliency in the ring and also by reason vehlmoV ing-the ends of said ring away from each "other to expand said ring, and transverse of the retracting springs 20, '12] and :22. lihe 5.; spring 20 extends between the end portions of the ring while the springs 2| and 22 extend-between I the leadin e d o heaupper nd slo h e an h kin p at I figu e sclo es another emb dimen s f m rinv nti n in w ich -fourr-i ictiontmemb s 2 1.24, .25 and 26 late used, insteadsof two friction .mem- (hers, as :in the modification illustrated in figures J to 4;, inclusive. Eachof'ithese ,friction memanchors for the ends of said ring in different directions of rotation of said drum, an actuator for relatively moving the ends of said ring away from each other to expand said ring, and members extending through and connecting said brake shoes and ring for converting'th torque of said brake shoes into an expanding force for said ring.

4, A brake comprising'a brake drum, T-section ,brake' shoes, ',a' flexible transversely split U-sec- -tion ring embracingthe webs of "said brake shoes I and expansible to force said brake shoes against "said drum, one of said brake shoes bridging the ,gap between the ends of said ring, anchor means for the ends of said ring in different directions f :r o tation-of said drum, an actuator for relapins' extending through the webs of said brake shoes and the legs of said ring for converting the torque of said brake shoes into an expand- I ing -,f;o11ce :for said ring.

bars comprises a Fri-section brakashoe theweb'sof 1 which isuembraced by the Ll-section expansible ring 21 which is formed .in the same .manner as .the ring '1, with theexception that it is anchored .a-tsits .ends between the wheel .cylinderlzs and the raicial flange of the friction member 23 "by the anchor-pins 19. The .web of 111 friction member 23 is .cut .awayto accommodate the anchor pins 1 r ,andtalso the rivets which serve'lto secure the end I .of the reinforcements 13D and the ringjl, It will he. noted that the connectionlbetween the. friction .rnembersand the ring ,for converting thetorgue Qf each .of the friction -mernhers .toianrexpanding iorce ior the ring .are located .nearer (one ,end. of each of the friction mernbers \thanthevother end. T-hisjs preferably the trailingiendso that a'subof each friction member .canheutilized. I 7' 1 I 'WhatIclaim as myinventionis': I I I11. Abrake comprising .albrake d vas ann -lar. series of frictio mem er a lexible n transversely split in one ,zone .onlyand expansihle', 'to'iorce said friction zmembe'rs" against said or .drum, means iorrelatively (moving the ends of members when a ain txsaid .drnm into an 3 paneling force for said ring.

2- i bra compris n .a brak '..me .nbe a f x b e transversely sp it r ngiexr pansible to foigcelsaid friction members against s id d m ne o s idr tion,r ernbersib idsin the gap between the endssqf saidringanchors for the ends of said ring'in different directions Qf lO 'tation oftsaid drumgneans for relatively'rnoving e e ds o s dmins away roma t ertoexpand said ring, and connections 'betwejenjsaid .dru n, friction v(i5 an expanding force forisaid expansible device.

-;5. A brake ;.comprising :a brake drum, brake shoes, a .-fiexible transversely split ring expansibie to forcesaid brake shoes in angularly spaced mones .againstsaid drum, oneof saidvbrake-shoes bridging the gap between the ends of said ,ring, reihforeing,members secured tothe-ends of said li ing and having generally ,radially vinwardly ex- -ttending projections, anchor means between .said 113103 actions, I an. actuator between; said projections for-expanding saidring, i and ccnnectionsbetween said brake shoes and ring for converting the torque ofsaid brakeshoesinto, anlexpandingjorce for said;ring. a V

6 1A brake comprising a brake drum, .brake shoes, va ,flexible transversely splitring expansible to ,force, said .hr'ake shoes at .angularly "spaced zones iagainst saiddrum, ,one Lof said ibrake shoes bridging the gap between.thevendsmfrsaid ring, reinforcements at the ends "of said ringliaving generally-radially inwardly extending .proiec- '',tions, an actuator between said projections ,for

expanding said ring, anchor -means ,radially outwardly of said actuator engageable withIsaid Treiinforcements, and connections between :said brake shoes and ring for converting "-the torque of rsai d brake shoes into-an expanding .forcezfor said ring. I

7. A brake comprising a brake drum, an 16X- pansible gieviee having :spa'ced ends, an annular series of friction-members.encirclingsaid expansible device ,and having friction faces engageable {Withsaid vdrum-the portionof said friction'mem. .bers at one side 'of the gap between :the ends-pf isaidiexpansible 1 device being connected-across the gap 'to the portion of" said friction vmembers rat the othe'rside ofthe gap,.anchorstforrtheispacefl ends of said rexpansible' device in difierentrdirem tionsiof'vrotation of saiddrum, means :for'rela- -tively moving the spaceden'dsiofsaid expansible device away from each other itoexpandsaidxem pansible device, and connections between said friction .members and expansible device for y confr ti0 m be s "and n's m e tin th torque of said frictionmembers'into an expanding portions of said brake shoes and; ,expansible to forcesaid brake shoes against said. drum, oneof said brake shoes having an "integral portion bridgingthegap between the ends gfisaid'ring, I

averting the torque of said friction members 'into I 8. A brake ccrnp'risinga-br-ake drum, friction members, I a flexible transversely split ringexpansible to force Fsaid friction members against said "drum, one of said friction members bridging the gap between the ends of saidring-anchor means for' s'aiduing, means for relatively moving 'the "ends of said ring away from each other to ;ex-

pand' said ring, and connections between said friction members and ring "for converting the torque of said friction members into expanding force for said ring.

9. A brake comprising a brake drum, a flexible expansible device having separable ends, friction members movable by said device against said drum, one of said friction members bridging the ends of said device, anchor means for the ends of said device in different directions of rotation 

